A simple cell is a device that converts chemical energy into electrical energy. A simple electric cell consists of two electrodes (two different metals) and an electrolyte solution (acid or alkali solution or salt solution)

How simple electric cells work:

The electrodes are made of two different metals

The more reactive (electropositive) metal tends to undergo oxidation and gives up electrons readily. It will become the anode (negative electrode).

The less reactive metal will become the cathode (positive electrode), as it has a weaker tendency to lose electrons.

The cell voltage depends on the positions of the metals in the reactivity series. The further apart the metals are in the reactivity series, the bigger the voltage of the cell.

Example Of A Simple Electric Cell

Since zinc is more reactive than copper, oxidation will occur at the zinc electrode. Zinc will become the anode. Each zinc atom loses two electrons and is oxidised to a zinc ion. Zinc dissolves into the acid solution.

Electrons will flow through the external wire to the copper metal. Hence, copper will become the cathode as reduction will occur at the copper electrode. Hydrogen ion from the acid solution will receive the electrons. Each hydrogen ion receives one electron and is reduced to hydrogen. Bubbles of hydrogen gas are formed at the copper surface.

Note that this reaction converts chemical energy into electrical energy.

Second Example Of A Simple Electric Cell

In this simple electric cell, two different metals and two different electrolyte solutions are used. Due to the usage of two different electrolyte solution, the end result will be different from the case above.

Since zinc is more electropositive than copper, zinc will become the anode. Each zinc atom loses two electrons and is oxidised to a zinc ion. Zinc dissolves into the acid solution.

What Others Are Saying:

Why, in the simple cell with one beaker, do the electrons flow through the wire in the first place?

Couldn’t the redox reaction occur between the Zn(s) and the Sulfuric Acid to create Zinc Sulfate and Hydrogen gas at the metal? As in, the electron transfer occurs where the Zinc and acid touch? Like why do the electrons travel through the wire when they can be tranferred more efficiently?

I can see why this isn’t a problem in the cell with the salt bridge, though, as the solutions are separated.

thanks for the help though I was a little confused at first concerning :anode (negatively charged) and cathode (positively charged) . but now i think am catching up. So what are the differences between a simple cell and an electrical cell?

Umm I think there is a little mistake here. the negative electrode is called cathode, and the positive one is called anode.

Quote : The more reactive (electropositive) metal tends to undergo oxidation and gives up electrons readily. It will become the anode (negative electrode). The less reactive metal will become the cathode (positive electrode), as it has a weaker tendency to lose electrons.

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